Computerized heart rate analysis in the selection of therapy for patients with arterial hypertension

Abstract

According to the World Health Organization (WHO), over 1 billion people are overweight and 600 million are obese, with metabolic syndrome (MS) affecting 35% of adults in the US and 20-25% in Europe. MS patients require appropriate therapy with comorbidity in mind, which requires further study and optimization. As part of the study, we conducted Holter ECG monitoring (HM) of patients with MS. MS was diagnosed on the basis of the MTP 3rd revision criteria. Additional criteria were AH, elevated triglyceride levels, decreased HDL cholesterol levels, impaired glucose tolerance (IGT), impaired fasting glycemia (EGS), and combined EGS/IGT disorders. MS was diagnosed based on 3 criteria: 1 main and 2 additional ones.Design. A total of 154 patients were examined in in-patient setting. They were subdivided into 2 main groups: Group I - patients with MS receiving β-blockers (n-97) to treat AH; Group II - patients with MS not receiving β-blockers (n-57).Each main group was divided according to the degree of obesity according to the WHO classification. Each patient underwent HM with programmed computer analysis of the wave spectrum of the obtained data and allocation of frequencies - 0.004-0.08 Hz (very low frequency - VLF); 0.09-0.16 Hz (low frequency - LF); 0.17-0.5 Hz (high frequency - HF) more than 0.5 Hz (ultra-low frequency waves - ULF); two coefficients are calculated - LF/HF (vagosympathetic balance coefficient) - ratio of low frequency waves power (LF) to high frequency waves power (HF), and centralization index (CI) - ratio of central regulation circuit activity to autonomic one (LF+VLF/HF).Results. Analysis found changes in HF, LF, and ULF domains of HRV spectrum, indicating transition to a more energy-intensive level of control and depletion of regulatory mechanisms. ULF(%) values above 6.9 require correction with β-blockers. The study found ULF% and VLF% values to be higher in the non-β-blocker group and administration of β-blockers resulted in normalization of indexes with the index of centralization and vagosympathetic balance. In patients receiving β-blockers, the values of these parameters corresponded to those of patients with normal body weight. In MS patients not receiving β-blockers, ULF% was 50% higher and VLF was 18% higher than in the normal weight group. The centralization index was elevated to 3.5. Administration of drugs to 17 patients in group II resulted in normalization of the indexes and achievement of the same values as in group I patients. At the dynamic follow-up for 2 years, Group I patients had no cardiovascular events. The 40 patients who refused to change therapy had no change in HM values and 27% of these patients had acute cardiovascular events at 2 years.Conclusion:Daily ECG monitoring with assessment of ULF%, VLF% and IC indices is a more subtle method of investigation, which allows to detect latent disorders of regulatory mechanisms (with seeming clinical well-being) in patients with disorders of these indices the risk of acute cardiovascular events development remains high. The control of ULF%, VLF% and IC index by HM-ECG method allows to change the therapy in time and to obtain a better result.